A construction method for pre-grouting reinforcement of underground continuous wall joints

Abstract

The present invention provides a construction method for pre-grouting reinforcement of underground continuous wall joints, comprising the following steps: S100. digging a continuous wall groove, including digging a plurality of straight groove sections at equal intervals along a planned position, and digging arc groove sections with the same structure between each adjacent straight groove section, wherein the arc convex surface of each arc groove section faces the external soil layer, and the concave surface faces the construction space; S200. prefabricating a continuous wall on the ground, and prefabricating a plane prefabricated wall and an arc prefabricated wall on the ground respectively; S300. successively lowering the plane prefabricated wall and the arc prefabricated wall, first lowering the plane prefabricated wall into the straight groove section, and then lowering the arc prefabricated wall into the arc groove section, and forming a closed joint structure at the inlaying and matching between the walls; S400. pre-grouting reinforcement in the closed joint structure to form a cast-in-place column structure. Through the provided construction method, the anti-leakage performance of the joints of the underground continuous wall is effectively improved, and the connection firmness of the joints and the stability of the overall structure are improved.

Description

Technical Field

[0001] The invention relates to the technical field of underground continuous wall construction, and in particular provides a method for pre-grouting and reinforcing a joint of an underground continuous wall. Background Art

[0002] The underground continuous wall is a commonly used enclosure and waterproof structure. It serves as a supporting structure during the construction phase and also as the exterior wall of the future structure. It has the advantages of good structural continuity and high overall rigidity. As an important form of underground continuous wall, the prefabricated underground continuous wall is prefabricated on the ground in sections, and then trenches are dug where they are needed to be constructed and used. The prefabricated sections are transferred and installed in the trenches. Each section of the underground continuous wall is integrally formed together, which can maintain a high strength of the single unit, fast construction speed, and strong adaptability to the on-site environment.

[0003] At present, most common prefabricated segments are flat plate structures, and the joints are flat joints close to each other. The joints between adjacent prefabricated structural segments are the weak links of this prefabricated underground continuous wall. After long-term practice, it has been found that the above-mentioned underground continuous wall has the following technical problems:

[0004] There is a shortcoming of poor anti-leakage performance. The seepage water from the external strata can easily leak from the joints to the construction space inside the underground continuous wall, making the underground continuous wall's blocking function ineffective. In order to improve the anti-leakage performance, at present, the construction site mostly adopts the method of pouring concrete mortar into the joints to seal the joints. At that time, this flat joint could not accommodate a large amount of concrete mortar, and the sealing process was difficult. During the pouring process, the concrete mortar was difficult to be concentrated in the flat joints and leaked out to the surrounding strata and voids. It was difficult to solidify to form an effective sealing structure.

[0005] The current prefabricated structure segments are flat plate structures, with poor connection firmness and poor lateral pressure resistance between the prefabricated structure segments. In addition, the structural stability in the stratum is poor, and the ability to withstand lateral forces perpendicular to the underground continuous wall is poor. Especially in complex geological conditions such as sandy soil strata, when one side of the underground continuous wall is a soil layer structure and the other side is a construction space, the lateral force of the soil layer structure can easily cause deformation, dislocation, and cracking at the joints, and even the underground continuous wall as a whole to tilt, which cannot play an effective support role.

[0006] In summary, the above-mentioned technical problems of prefabricated underground continuous walls not only reduce the anti-leakage performance, but also have poor connection firmness and poor stability of the overall structure in the stratum, which affects the promotion and application of this type of underground continuous wall. These are technical problems that the industry urgently needs to solve. Summary of the invention

[0007] To this end, the present invention provides a construction method for pre-grouting reinforcement of underground continuous wall joints to improve the anti-leakage performance of the joints of the prefabricated underground continuous wall, and improve the connection firmness of the joints and the stability of the overall structure.

[0008] In order to achieve the above object, the present invention provides a method for pre-grouting reinforcement of underground continuous wall joints, which is characterized by comprising the steps of:

[0009] S100. Digging of continuous wall trench:

[0010] The method comprises excavating a plurality of straight trench sections at equal intervals along the planned position, and excavating arc-shaped trench sections with the same structure between adjacent straight trench sections, wherein the arc-shaped convex surface of each arc-shaped trench section faces the external soil layer, and the concave surface faces the construction space, and the two ends of the arc-shaped trench section are respectively connected to the adjacent straight trench sections;

[0011] S200. Ground prefabricated continuous wall:

[0012] Prefabricate a flat prefabricated wall and an arc-shaped prefabricated wall on the ground respectively, and the ends of the flat prefabricated wall and the arc-shaped prefabricated wall are embedded and adapted;

[0013] S300. Insert the flat prefabricated wall and the curved prefabricated wall in sequence:

[0014] First, lower the plane prefabricated wall into the straight groove section, and then lower the arc-shaped prefabricated wall into the arc-shaped groove section, keeping the two ends of the arc-shaped prefabricated wall in an inlay fit with the plane prefabricated wall, and forming a closed joint structure at the inlay fit between the arc-shaped prefabricated wall and the plane prefabricated wall;

[0015] S400. Pre-grouting reinforcement in the closed joint structure of flat prefabricated wall and curved prefabricated wall:

[0016] The soil in the entire depth of the closed joint structure is cleaned and concrete slurry is poured to form a cast-in-place column structure to reinforce the connection and prevent water seepage between the flat prefabricated wall and the curved prefabricated wall.

[0017] Furthermore, the steps of lowering the plane prefabricated wall and the curved prefabricated wall include:

[0018] S310. The plane prefabricated wall is driven downward to a certain set depth by applying downward pressure and vibration;

[0019] S320. Insert the curved wall between adjacent planar prefabricated walls, and make the curved wall fit in with the planar prefabricated walls at both ends;

[0020] S330. Drive the arc-shaped prefabricated wall and the plane prefabricated wall to a predetermined depth through external force.

[0021] Furthermore, vertically extending convex structures are provided at both ends of the plane prefabricated wall, and vertically extending concave structures adapted to the convex structures are provided at both ends of the arc-shaped prefabricated wall. During the process of lowering the arc-shaped prefabricated wall, the concave structures slide and cooperate with the convex structures to guide the lowering of the arc-shaped prefabricated wall; or,

[0022] Concave structures extending vertically are arranged at both ends of the plane prefabricated wall, and convex structures extending vertically and matching with the concave structures are arranged at both ends of the arc-shaped prefabricated wall. During the process of lowering the arc-shaped prefabricated wall, the convex structure and the concave structure slide and cooperate with each other to guide the lowering of the arc-shaped prefabricated wall.

[0023] Furthermore, vertical guide grooves are symmetrically arranged on both sides of the inner part of the concave structure, and vertical guide blocks are symmetrically arranged on both sides of the front end of the convex structure. When the concave structure and the convex structure are connected, the vertical guide grooves on adjacent sides slide with the vertical guide blocks.

[0024] Furthermore, a first semicircular groove extending vertically is provided on the front end surface of the convex structure, and a second semicircular groove extending vertically is provided on the inner bottom surface of the concave structure. The first semicircular groove and the second semicircular groove constitute a vertically penetrating circular hole as a closed joint structure, and concrete slurry is poured into the circular hole to carry out connection reinforcement and water seepage prevention between the flat prefabricated wall and the arc prefabricated wall.

[0025] Furthermore, after the plane prefabricated wall and the arc prefabricated wall are lowered to a predetermined depth, the soil in the circular hole is rotary excavated by a drill rod machine, and high-pressure cleaning water is delivered into the circular hole by the drill rod to drive the soil in the circular hole to flow upward from the bottom and be discharged from the top of the circular hole; then the drill rod is continued to be driven downward along the circular hole to drill into the stratum to form a bottom countersunk hole with a depth greater than that of the prefabricated wall, and high-pressure cleaning water is delivered to the bottom again to discharge the soil in the bottom countersunk hole from the circular hole.

[0026] Furthermore, concrete slurry is transported to the bottom countersunk hole, and concrete is injected into the circular hole from bottom to top, so as to perform integrated concrete pouring of the bottom countersunk hole and the circular hole, thereby realizing anchoring of the plane prefabricated wall and the arc prefabricated wall in the stratum.

[0027] Furthermore, during the ground prefabrication process of the plane prefabricated wall and the arc-shaped prefabricated wall, a first half spiral groove arranged along a vertical array is prefabricated in the first semicircular groove, and a second half spiral groove arranged along a vertical array is prefabricated in the second semicircular groove. When the heights of the plane prefabricated wall and the arc-shaped prefabricated wall are adjusted to be consistent, the first half spiral groove and the second half spiral groove form a continuous spiral continuous groove structure, and concrete slurry is poured into the circular hole with the spiral continuous groove structure to reinforce the connection between the plane prefabricated wall and the arc-shaped prefabricated wall to avoid vertical dislocation.

[0028] Furthermore, a spiral reinforcing steel bar having the same rotation direction as the spiral structure is manufactured on the ground, and after adjusting the height of the planar prefabricated wall and the arc-shaped prefabricated wall structure to be consistent, the spiral reinforcing steel bar is screwed into the spiral continuous groove structure from the ground, and then concrete slurry is poured into the circular hole to reinforce the connection between the spiral reinforcing steel bar and the planar prefabricated wall and the arc-shaped prefabricated wall.

[0029] Furthermore, the lower end of the spiral reinforcement steel bar is screwed into the bottom countersunk hole along the spiral structure, concrete slurry is transported to the bottom countersunk hole, and concrete is injected into the circular hole from bottom to top, so as to perform integrated concrete pouring of the bottom countersunk hole and the circular hole, and the continuous wall is anchored in the stratum through the spiral reinforcement steel bar and concrete.

[0030] Compared with the prior art, the technical advantages of the underground continuous wall joint pre-grouting reinforcement construction method provided by the present invention are at least reflected in:

[0031] 1. The plane prefabricated wall and the arc prefabricated wall are arranged at intervals and their ends are embedded with each other, forming a closed joint structure extending vertically between the plane prefabricated wall and the arc prefabricated wall. After being lowered to a set depth, concrete slurry is poured in the closed joint structure. The closed joint structure improves the capacity of holding concrete slurry, avoids the problem of slurry flowing out during the pouring process, and avoids the infiltration of external soil layers and groundwater during the pouring process. It can form a cast-in-place column structure with high structural strength, so that the joints between the plane prefabricated wall and the arc prefabricated wall maintain connection strength and anti-leakage ability;

[0032] 2. The poured concrete slurry not only fills the closed joint structure, but also flows into the tortuous and narrow gaps connected to the closed joint structure, increasing the connection area of ​​the joints between the flat prefabricated wall and the curved prefabricated wall. The concrete slurry in the closed joint and the narrow gaps on both sides is integrated, which improves the bonding strength and forms a solid integrated structure of the curved prefabricated wall and the flat prefabricated wall, effectively preventing the occurrence of dislocation and cracking problems at the joints in the stratum;

[0033] 3. First lower the plane prefabricated wall into the straight trench section, and then lower the arc prefabricated wall into the arc trench section. The plane prefabricated wall remains in a vertical state, and the arc prefabricated wall that is subsequently lowered is supported and constrained, so that the entire wall remains vertical. The convex surface of the arc prefabricated wall faces the external soil layer, and the concave surface faces the construction space. This can not only improve the ability to resist the external soil structure and avoid the occurrence of overall tilting problems in the soil structure, but also the convex surface of the arc prefabricated wall can disperse the lateral squeezing force of the soil layer, thereby improving the ability to resist soil pressure. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] The drawings described herein are used to provide a further understanding of the present invention and constitute a part of this application. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0035] Figure 1 It is a flowchart of the underground continuous wall joint pre-grouting reinforcement construction method provided by an embodiment of the present invention;

[0036] Figure 2 It is a flowchart of inserting a flat prefabricated wall 21 and a curved prefabricated wall 22 according to an embodiment of the present invention;

[0037] Figure 3 Schematic diagram of a planar prefabricated wall and an arc-shaped prefabricated wall structure provided according to an embodiment of the present invention; (connection state)

[0038] Figure 4 Schematic diagram of a flat prefabricated wall and an arc prefabricated wall structure provided according to an embodiment of the present invention; (split state)

[0039] Figure 5 is a structural schematic diagram of a plane prefabricated wall provided according to an embodiment of the present invention;

[0040] Figure 6 yes Figure 5 A local enlarged structural schematic diagram of A;

[0041] Figure 7 A schematic structural diagram of a curved prefabricated wall provided according to an embodiment of the present invention;

[0042] Figure 8 yes Figure 7 A schematic diagram of the local enlarged structure at C;

[0043] Fig. 9 is a front view of a flat prefabricated wall and an arc-shaped prefabricated wall provided in an embodiment of the present invention being installed in a continuous wall groove;

[0044] Fig.10 It is a top view of the installation of a flat prefabricated wall and an arc prefabricated wall in a continuous wall groove according to an embodiment of the present invention.

[0045] Description of the accompanying drawings:

[0046] 11-straight trench section, 12-arc trench section, 13-external soil layer, 14-construction space;

[0047] 21- plane prefabricated wall, 22- arc-shaped prefabricated wall, 201- convex structure, 202- concave structure, 203- vertical guide groove, 204- vertical guide block, 205- first semicircular groove, 206- second semicircular groove, 207- first semi-spiral groove, 208- second semi-spiral groove, 209- circular hole;

[0048] 3- Cast-in-place column structure;

[0049] 4-Bottom countersunk hole;

[0050] 5-Spiral reinforcement bars.

[0051] It should be understood that the size of each part shown in the accompanying drawings is not drawn according to the actual proportional relationship. In addition, the same or similar reference numerals represent the same or similar components. DETAILED DESCRIPTION

[0052] At present, most common prefabricated segments are flat-plate structures, and the joints are flat straight joints close to each other. The joints between adjacent prefabricated structure segments are the weak links of this prefabricated underground continuous wall, which not only reduces the anti-leakage performance, but also has poor connection firmness and poor stability of the overall structure in the stratum, affecting the promotion and application of this underground continuous wall.

[0053] To this end, the present invention provides a construction method for pre-grouting reinforcement of underground continuous wall joints, wherein a plurality of straight groove sections are dug at equal intervals along the planned position, and arc-shaped groove sections with the same structure are dug between adjacent straight groove sections, wherein the arc-shaped convex surface of each arc-shaped groove section faces the external soil layer, and the concave surface faces the construction space; a plane prefabricated wall and an arc-shaped prefabricated wall are prefabricated on the ground respectively; the plane prefabricated wall and the arc-shaped prefabricated wall are successively lowered, a closed joint structure is formed at the joints between the walls, and pre-grouting reinforcement is performed in the closed joint structure to form a cast-in-place column structure, thereby effectively improving the anti-leakage performance of the joints of the underground continuous wall, and improving the connection firmness of the joints and the stability of the overall structure.

[0054] Various exemplary embodiments of the present disclosure will now be described in detail with reference to the accompanying drawings. The description of the exemplary embodiments is merely illustrative and is in no way intended to limit the present disclosure and its application or use. The present disclosure can be implemented in many different forms and is not limited to the embodiments described herein. These embodiments are provided to make the present disclosure thorough and complete and to fully express the scope of the present disclosure to those skilled in the art. It should be noted that unless otherwise specifically stated, the relative arrangement of the components and steps, and the composition of the materials described in these embodiments are merely exemplary and not intended to be limiting.

[0055] Various exemplary embodiments of the present invention will now be described in detail with reference to the accompanying drawings. The description of the exemplary embodiments is merely illustrative and is in no way intended to limit the present invention and its application or use. The present invention can be implemented in many different forms and is not limited to the embodiments herein. The terms "first", "second", etc. that appear in the invention are only for the convenience of description to distinguish different components with the same name and do not indicate a sequential or primary-secondary relationship. In the present invention, when a specific device is described as being located between a first device and a second device, there may or may not be an intermediate device between the specific device and the first device or the second device.

[0056] Embodiment 1:

[0057] like Figures 1 to 10 As shown, the present invention provides a method for pre-grouting reinforcement of underground continuous wall joints, comprising the steps of:

[0058] S100. Digging of continuous wall trench:

[0059] The method comprises excavating a plurality of straight groove sections 11 at equal intervals along the planned position, and excavating arc-shaped groove sections 12 with the same structure between adjacent straight groove sections 11, wherein the arc-shaped convex surface of each arc-shaped groove section 12 faces the external soil layer 13, and the concave surface faces the construction space 14, and the two ends of the arc-shaped groove section 12 are respectively connected to the adjacent straight groove sections 11;

[0060] S200. Ground prefabricated continuous wall:

[0061] A plane prefabricated wall 21 and an arc-shaped prefabricated wall 22 are prefabricated on the ground respectively, and the ends of the plane prefabricated wall 21 and the arc-shaped prefabricated wall 22 are embedded and adapted;

[0062] S300. The flat prefabricated wall 21 and the curved prefabricated wall 22 are successively lowered:

[0063] First, lower the plane prefabricated wall 21 into the straight groove section 11, and then lower the arc-shaped prefabricated wall 22 into the arc-shaped groove section 12, keeping the two ends of the arc-shaped prefabricated wall 22 in engagement with the plane prefabricated wall 21, and the engagement between the arc-shaped prefabricated wall 22 and the plane prefabricated wall 21 forms a closed joint structure;

[0064] S400. Pre-grouting reinforcement in the closed joint structure of the flat prefabricated wall 21 and the curved prefabricated wall 22:

[0065] The soil in the closed joint structure is cleaned and concrete slurry is poured to form a cast-in-place column structure 3 to reinforce the connection between the flat prefabricated wall 21 and the arc-shaped prefabricated wall 22 and prevent water seepage.

[0066] The underground continuous wall joint pre-grouting reinforcement construction method provided:

[0067] The plane prefabricated wall 21 and the arc-shaped prefabricated wall 22 are arranged at intervals and their ends are interlocked with each other. After being lowered to a set depth, concrete slurry is poured in the closed joint structure. The closed joint structure improves the capacity to accommodate concrete slurry, avoids the problem of slurry leakage during pouring, and avoids the influence of infiltration of external soil layers and groundwater during pouring. It can form a cast-in-place column structure 3 with high structural strength, so that the joints between the plane prefabricated wall 21 and the arc-shaped prefabricated wall 22 maintain connection strength and anti-leakage ability.

[0068] like Figure 2 As shown, during the implementation process, the steps of lowering the plane prefabricated wall 21 and the arc prefabricated wall 22 include:

[0069] S310. The plane prefabricated wall 21 is driven downward to a certain depth by applying downward pressure and vibration;

[0070] S320. Insert the curved wall between the adjacent planar prefabricated walls 21, and make the curved wall fit with the planar prefabricated walls 21 at both ends;

[0071] S330. Drive the arc-shaped prefabricated wall 22 and the plane prefabricated wall 21 to a predetermined depth through external force.

[0072] Through the above steps, the plane prefabricated wall 21 remains in a vertically lowered state, and supports and constrains the subsequently lowered arc-shaped prefabricated wall 22, so that the entire wall remains vertical. Combined with the arrangement of the convex surface of the arc-shaped prefabricated wall 22 facing the external soil layer 13 and the concave surface facing the construction space 14, it can not only improve the ability to resist the external soil layer structure and avoid the occurrence of the overall tilting problem in the soil layer structure, but also the convex surface of the arc-shaped prefabricated wall 22 can disperse the lateral squeezing force of the soil layer, thereby improving the ability to resist the soil layer pressure.

[0073] Embodiment 2:

[0074] like Figures 3 to 8 As shown, on the basis of the first embodiment, a concave-convex connection structure is provided between the joints of the plane prefabricated wall 21 and the arc-shaped prefabricated wall 22, and a circular hole is provided in the internal component of the connection structure to accommodate the injected concrete slurry. The specific optimization is as follows:

[0075] During implementation, the following structure may be adopted: vertically extending convex structures 201 are provided at both ends of the planar prefabricated wall 21 , and vertically extending concave structures 202 adapted to the convex structures 201 are provided at both ends of the arc-shaped prefabricated wall 22 .

[0076] It can also be a structure in which a concave structure 202 extending vertically is provided at both ends of the plane prefabricated wall 21, and a convex structure 201 extending vertically and matching the concave structure 202 is provided at both ends of the arc-shaped prefabricated wall 22.

[0077] Preferably, vertical guide grooves 203 are symmetrically arranged on both sides of the inner part of the concave structure 202, and vertical guide blocks 204 are symmetrically arranged on both sides of the front end of the convex structure 201. When the concave structure 202 is connected to the convex structure 201, the vertical guide grooves 203 on adjacent sides slide in cooperation with the vertical guide blocks 204.

[0078] By the mutual embedding of the convex structure 201 and the concave structure 202, the occurrence of flat seams between the plane prefabricated wall 21 and the arc-shaped prefabricated wall 22 as prefabricated structure segments is avoided, and during the process of lowering the plane prefabricated wall 21 and the arc-shaped prefabricated wall 22, the concave structure 202 can be kept in sliding cooperation with the convex structure 201 to guide the lowering of the arc-shaped prefabricated wall 22, and the convex structure 201 and the concave structure remain connected to form a closed joint structure for accommodating the pouring of concrete slurry in the middle, and tortuous narrow gaps are formed on both sides of the closed joint structure.

[0079] Concrete slurry is poured at the upper end of the closed joint structure. The poured concrete slurry not only fills the closed joint structure, but also flows into the tortuous and narrow gaps connected to the closed joint structure, thereby increasing the connection area at the joints of the flat prefabricated wall 21 and the arc-shaped prefabricated wall 22. The concrete slurry in the closed joint and in the narrow gaps on both sides is an integrated structure, which improves the bonding strength and effectively prevents the occurrence of dislocation and cracking problems at the joints in the stratum.

[0080] Embodiment three:

[0081] like Figures 3 to 10 As shown, the structure is optimized on the basis of the second embodiment. Specifically, a first semicircular groove 205 extending vertically is provided on the front end surface of the convex structure 201, and a second semicircular groove 206 extending vertically is provided on the inner bottom surface of the concave structure 202. The first semicircular groove 205 and the second semicircular groove 206 form a vertically through circular hole 209 as a closed joint structure, and concrete slurry is poured into the circular hole 209 to carry out connection reinforcement and water seepage prevention between the flat prefabricated wall 21 and the arc prefabricated wall 22.

[0082] Based on the circular hole structure at the joint, it is convenient for the drill rod to enter the interior for rotation and cleaning, as well as the subsequent pouring of concrete slurry. The poured slurry forms a cylindrical structure in the circular hole structure, which can improve the bonding force between the flat prefabricated wall 21 and the arc prefabricated wall 22. The cylindrical structure itself has a strong bearing capacity and can improve the overall structural strength of the underground continuous wall.

[0083] On the basis of the circular hole structure, the structure is further optimized, and a bottom countersunk hole is formed by digging downward from the circular hole. By pouring concrete slurry into the bottom countersunk hole of the circular hole, the plane prefabricated wall 21 and the arc prefabricated wall 22 are anchored in the stratum. The specific implementation is as follows:

[0084] After the plane prefabricated wall 21 and the arc-shaped prefabricated wall 22 are lowered to a predetermined depth, the soil in the circular hole 209 is rotary excavated by a drill rod machine, and high-pressure cleaning water is delivered to the circular hole 209 by the drill rod, driving the soil in the circular hole 209 to flow upward from the bottom and be discharged from the top of the circular hole 209; then the drill rod is continued to be driven downward along the circular hole 209 to drill into the stratum, forming a bottom countersunk hole 4 with a depth greater than that of the prefabricated wall, and high-pressure cleaning water is delivered to the bottom again to discharge the soil in the bottom countersunk hole 4 from the circular hole 209.

[0085] Based on the above embodiment, concrete slurry is transported to the bottom countersunk hole 4, and concrete is injected into the circular hole 209 from bottom to top, so that the bottom countersunk hole 4 and the circular hole 209 are integrally poured with concrete to realize the anchoring of the plane prefabricated wall 21 and the arc prefabricated wall 22 in the stratum.

[0086] Embodiment 4:

[0087] like Figures 3 to 10 As shown, based on the structures of the second and third embodiments, the structure is further optimized, a continuous spiral groove structure is formed in the circular hole, and a spiral reinforcing steel bar is screwed into the continuous spiral groove to improve the connection strength of the concrete structure in the circular hole and the countersunk hole. The specific implementation is as follows:

[0088] During the ground prefabrication process of the plane prefabricated wall 21 and the arc-shaped prefabricated wall 22, a first semi-spiral groove 207 arranged along a vertical array is prefabricated in the first semicircular groove 205, and a second semi-spiral groove 208 arranged along a vertical array is prefabricated in the second semicircular groove 206. When the heights of the plane prefabricated wall 21 and the arc-shaped prefabricated wall 22 are adjusted to be consistent, the first semi-spiral groove 207 and the second semi-spiral groove 208 form a continuous spiral continuous groove structure, and concrete slurry is poured into the circular hole 209 with the spiral continuous groove structure.

[0089] Based on this embodiment, compared with the smooth circular hole structure, a continuous spiral continuous groove structure is set in the circular hole, and the poured concrete slurry not only enters the circular hole, but also enters the spiral continuous groove structure. After the concrete slurry solidifies, the concrete in the spiral continuous groove is integrated with the concrete structure in the circular hole, which can improve the vertical bonding force between the flat prefabricated wall 21 and the arc-shaped prefabricated wall 22, and reinforce the connection between the flat prefabricated wall 21 and the arc-shaped prefabricated wall 22 to avoid vertical dislocation.

[0090] Furthermore, in some preferred embodiments, spiral reinforcing steel bars are loaded into the spiral continuous groove, and the specific implementation is as follows: a spiral reinforcing steel bar 5 having the same rotation direction as the spiral structure is manufactured on the ground, and after adjusting the structural height of the flat prefabricated wall 21 and the arc-shaped prefabricated wall 22 to be consistent, the spiral reinforcing steel bar 5 is screwed into the spiral continuous groove structure from the ground, and then concrete slurry is poured into the circular hole 209.

[0091] By loading spiral reinforcing steel bars 5 into the spiral continuous groove structure, pouring slurry, and filling the solidified concrete slurry into the circular hole structure and the spiral continuous groove, a solidified connection between the spiral reinforcing steel bars 5 and the spiral continuous groove is achieved, and the connection reinforcement between the flat prefabricated wall 21 and the arc-shaped prefabricated wall 22 is increased, forming an integrated structure of the spiral reinforcing steel bars 5, the flat prefabricated wall 21 and the arc-shaped prefabricated wall 22, which can withstand greater top pressure and lateral force, improve the bearing capacity of the underground continuous wall, and is particularly suitable for the structural use of underground continuous walls with greater depths.

[0092] Furthermore, in some preferred embodiments, the lower end of the spiral reinforcement steel bar 5 is screwed into the bottom countersunk hole 4 along the spiral structure, concrete slurry is transported to the bottom countersunk hole 4, and concrete is injected into the circular hole 209 from bottom to top, and the bottom countersunk hole 4 and the circular hole 209 are integrally poured with concrete, and the continuous wall is anchored in the stratum through the spiral reinforcement steel bar 5 and concrete.

[0093] Based on this embodiment, the spiral reinforcing steel bar 5 can not only enhance the bonding force between the flat prefabricated wall 21 and the arc-shaped prefabricated wall 22, but also the spiral reinforcing steel bar 5 extends into the bottom countersunk hole 4 to form a steel bar footing in the bottom countersunk hole. After the concrete slurry is injected, the concrete slurry and the spiral reinforcing bar serving as the steel bar footing form an integrated structure.

[0094] Based on the above embodiments, a method for pre-grouting reinforcement of underground continuous wall joints is provided, which forms a closed joint structure extending vertically between the flat prefabricated wall 21 and the curved prefabricated wall 22, thereby improving the capacity to accommodate concrete slurry. The poured concrete slurry not only fills the closed joint structure, but also flows into the tortuous and narrow gaps connected to the closed joint structure, thereby increasing the connection area at the joint of the flat prefabricated wall 21 and the curved prefabricated wall 22, avoiding the problem of slurry leakage during the pouring process, and also avoiding the influence of the infiltration of external soil layers and groundwater during the pouring process.

[0095] Furthermore, the provided construction method can form a cast-in-place column structure 3 with high structural strength, forming a solid integrated structure of the arc-shaped prefabricated wall 21 and the plane prefabricated wall 22, effectively preventing the occurrence of dislocation and cracking problems at the joints in the stratum; maintaining the connection strength and anti-leakage ability at the joints between the plane prefabricated wall 21 and the arc-shaped prefabricated wall 22; and can improve the ability to resist the outer soil layer 13 and avoid the occurrence of overall tilting problems, and the protruding surface of the arc-shaped prefabricated wall 22 can disperse the lateral squeezing force of the soil layer, thereby improving the ability to resist the soil layer pressure.

[0096] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein, but these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for pre-grouting reinforcement of underground continuous wall joints, characterized in that: Includes steps: S100. Digging of continuous wall trench The method comprises excavating a plurality of straight groove sections (11) at equal intervals along the planned position, and excavating arc-shaped groove sections (12) with the same structure between adjacent straight groove sections (11), wherein the arc-shaped convex surface of each arc-shaped groove section (12) faces the external soil layer (13) and the concave surface faces the construction space (14), and the two ends of the arc-shaped groove section (12) are respectively connected to the adjacent straight groove sections (11); S200. Ground prefabricated continuous wall Prefabricating a flat prefabricated wall (21) and an arc-shaped prefabricated wall (22) on the ground respectively, wherein the ends of the flat prefabricated wall (21) and the arc-shaped prefabricated wall (22) are embedded and adapted; S300. The flat prefabricated wall (21) and the curved prefabricated wall (22) are successively lowered. First, the plane prefabricated wall (21) is lowered into the straight groove section (11), and then the arc-shaped prefabricated wall (22) is lowered into the arc-shaped groove section (12), and the two ends of the arc-shaped prefabricated wall (22) are kept in an inlaid fit with the plane prefabricated wall (21), so that the inlaid fit between the arc-shaped prefabricated wall (22) and the plane prefabricated wall (21) forms a closed joint structure; S400. Pre-grouting reinforcement in the closed joint structure between the flat prefabricated wall (21) and the curved prefabricated wall (22) Cleaning the soil in the closed joint structure and pouring concrete slurry to form a cast-in-place column structure (3) to connect and reinforce the flat prefabricated wall (21) and the curved prefabricated wall (22) and prevent water seepage; Convex structures (201) extending vertically are arranged at both ends of the planar prefabricated wall (21), and concave structures (202) extending vertically and matching with the convex structures (201) are arranged at both ends of the arc-shaped prefabricated wall (22); during the process of lowering the arc-shaped prefabricated wall (22), the concave structures (202) and the convex structures (201) are slidably matched to guide the lowering of the arc-shaped prefabricated wall (22); Vertical guide grooves (203) are symmetrically arranged on both sides of the interior of the concave structure (202), and vertical guide blocks (204) are symmetrically arranged on both sides of the front end of the convex structure (201); when the concave structure (202) and the convex structure (201) are connected, the vertical guide grooves (203) and the vertical guide blocks (204) on adjacent sides are slidably matched; A first semicircular groove (205) extending vertically is provided on the front end surface of the convex structure (201), and a second semicircular groove (206) extending vertically is provided on the inner bottom surface of the concave structure (202), wherein the first semicircular groove (205) and the second semicircular groove (206) form a vertically penetrating circular hole (209) as a closed joint structure, and concrete slurry is poured into the circular hole (209) to connect and reinforce the flat prefabricated wall (21) and the arc-shaped prefabricated wall (22) and prevent water seepage; After the plane prefabricated wall (21) and the arc-shaped prefabricated wall (22) are lowered to a predetermined depth, the soil in the circular hole (209) is rotary excavated by a drill rod machine, and high-pressure cleaning water is delivered to the circular hole (209) by the drill rod to drive the soil in the circular hole (209) to flow upward from the bottom and be discharged from the top of the circular hole (209); then the drill rod is driven to drill downward along the circular hole (209) into the stratum to form a bottom sink hole (4) with a depth greater than that of the prefabricated wall, and high-pressure cleaning water is delivered to the bottom again to discharge the soil in the bottom sink hole (4) from the circular hole (209); Concrete slurry is transported to the bottom countersunk hole (4), and concrete is injected into the circular hole (209) from bottom to top, so as to perform integrated concrete pouring of the bottom countersunk hole (4) and the circular hole (209), thereby achieving anchoring of the plane prefabricated wall (21) and the arc-shaped prefabricated wall (22) in the stratum; During the ground prefabrication of the planar prefabricated wall (21) and the arc-shaped prefabricated wall (22), a first half spiral groove (207) arranged along a vertical array is prefabricated in the first semicircular groove (205), and a second half spiral groove (208) arranged along a vertical array is prefabricated in the second semicircular groove (206); after the planar prefabricated wall (21) and the arc-shaped prefabricated wall (22) are adjusted to be of the same height, the first half spiral groove (207) and the second half spiral groove (208) form a continuous spiral continuous groove structure, and concrete slurry is poured into the circular hole (209) with the spiral continuous groove structure to connect and reinforce the planar prefabricated wall (21) and the arc-shaped prefabricated wall (22) to avoid vertical misalignment; A spiral reinforcing steel bar (5) having the same rotation direction as the spiral continuous groove structure is manufactured on the ground, and after adjusting the structural heights of the planar prefabricated wall (21) and the arc-shaped prefabricated wall (22) to be consistent, the spiral reinforcing steel bar (5) is screwed into the spiral continuous groove structure from the ground, and then concrete slurry is poured into the circular hole (209) to reinforce the connection between the spiral reinforcing steel bar (5) and the planar prefabricated wall (21) and the arc-shaped prefabricated wall (22); The lower end of the spiral reinforcement steel bar (5) is screwed into the bottom countersunk hole (4) along the spiral continuous groove structure, and concrete slurry is transported to the bottom countersunk hole (4). Concrete is injected into the circular hole (209) from bottom to top, and the bottom countersunk hole (4) and the circular hole (209) are integrally poured with concrete, so that the continuous wall is anchored in the stratum through the spiral reinforcement steel bar (5) and concrete.

2. The underground continuous wall joint pre-grouting reinforcement construction method according to claim 1 is characterized in that: The steps of lowering the flat prefabricated wall and the curved prefabricated wall include: S310. The plane prefabricated wall (21) is lowered, and the plane prefabricated wall (21) is driven downward to a certain set depth by applying downward pressure and vibration; S320. Insert the curved wall between the adjacent planar prefabricated walls (21), and make the curved wall fit in with the planar prefabricated walls (21) at both ends; S330. Drive the arc-shaped prefabricated wall (22) and the plane prefabricated wall (21) to a predetermined depth through external force.

3. The underground continuous wall joint pre-grouting reinforcement construction method according to claim 1 is characterized in that: Concave structures (202) extending vertically are arranged at both ends of the planar prefabricated wall (21), and convex structures (201) extending vertically and matching with the concave structures (202) are arranged at both ends of the arc-shaped prefabricated wall (22). During the process of lowering the arc-shaped prefabricated wall (22), the convex structure (201) and the concave structure (202) are slidably matched to guide the lowering of the arc-shaped prefabricated wall (22).

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